Patent GB-688293-A (GB)
Title: Lubricating oil composition
Inventor: MCLEAN DONALD HENRY
IPC: C10M135/04
Filed: 1950-06-19
Abstract: Sulphurized terpenes are made by reacting sulphur with a terpene or mixture of terpenes, the lower boiling components being removed from the reacted mixture by steam distillation at a temperature below the decomposition temperature of the sulphurized terpenes.  They are lubricating oil additives, cf. Group III.  Reaction temperatures mentioned are 135-200 DEG  C., preferably 170-180 DEG  C., and 1.5-2 atoms of S per mol. of terpene are used.  Other amounts of S specified are 20-35 per cent, preferably 25-30 per cent, and reaction times instanced are 5-10 hours, usually 6-7 hours.  Dipentene is the preferred terpene. Distillation temperatures should not substantially exceed 150 DEG  C. and are preferably below 130 DEG  C. e.g. 100-120 DEG  C.  Usually about 15-30 per cent of crude product is removed. Resins produced in the reaction are desirably removed by solvent precipitation before or after steam distillation.  Petroleum ether and pentane are specified solvents.  Preferably sulphurization is effected in the presence of a vulcanization accelerator, e.g. tetramethyl thiuram disulphide, mercaptobenzothiazole and diphenyl guanidine.  The amount of accelerator is conveniently less than 5 per cent and preferably 1-2 per cent.  In an example, dipentene and sulphur are heated at up to 175 DEG  C. in the presence of a mixture of mercaptobenzothiazole and diphenyl guanidine and the product treated by (a) blowing with nitrogen to remove H2S; (b) washing with 15 per cent caustic soda; (c) steam distilled to remove 30 per cent of light ends; (d) solvent precipitated to remove 12 per cent polymer; and (e) steam distilled and precipitated as in (c) and (d), treatments (a), (b) and (d) being for comparative purposes.ALSO:A lubricating oil composition comprises a lubricating oil, preferably a mineral lubricating oil, and a minor proportion of the product of the process wherein sulphur is reacted with a terpene or mixture of terpenes and the lower boiling components are removed from the reacted mixture by steam distillation at a temperature below the decomposition temperature of the sulphurized terpenes.  Usually about 15-30 per cent of crude product is removed.  Resins produced in the reaction are preferably removed by solvent precipitation either before or after steam distillation.  Preferably sulphurization is effected in the presence of a rubber vulcanization accelerator.  For details of the process (see Group IV(b)).  The additives are used in amounts of about 0.1-2 per cent, preferably about 0.3-0.5 per cent. Detergent additives may also be present, those mentioned being calcium mahogany sulphonates, calcium or barium phenates, zinc butyl or isopropyl benzoate, metal organo-phosphates and thiophosphates and preferably alkaline earth derivatives of alkyl phenol sulphides or sulphurized alkylated phenols.  Detergent additives may be used in amounts of about 1 to 5 per cent, preferably about 1.5 to 2.5 per cent.  In an example dipentene and sulphur are heated up to 175 DEG C for 8 1/2 hours in the presence of a mixture of mercaptobenzothiazole and diphenyl guanidine and the product treated by (a) blowing with nitrogen to remove H2S, (b) washing with 15 per cent caustic soda, (c) steam distilled to remove 30 per cent of light ends, (d) solvent precipitated to remove 12 per cent of polymer, and (e) steam disstilled and preciptated as in (c) and (d) and the products are engine tested as lubricants in admixture with a mineral oil containing 1.5 per cent of the barium salt of p-tert.-octyl phenol sulphide and 1.5 per cent of the products, it being shown that those of (c) and (e) give the best results